Indivior Presents New Data at CPDD Demonstrating that High Buprenorphine Exposure May Improve Treatment Outcomes in High Fentanyl Users

• A post-hoc analysis demonstrates that buprenorphine exposure with 300 mg SUBLOCADE® (buprenorphine extended-release) may improve treatment outcomes among opioid use disorder (OUD) patients with heavy fentanyl use¹
• Additional Indivior-funded research identified OUD treatment barriers in American Indian/Alaska Native (AI/AN) people who are often affected by higher drug overdose death rates compared to other racial and ethnic groups^2-5

RICHMOND, Va., June 19, 2025 –– Indivior PLC (Nasdaq: INDV) presented new findings this week at the College on Problems of Drug Dependence (CPDD) Annual Scientific Meeting. A post hoc analysis showed that patients with heavier fentanyl use experienced clinically meaningful improvements in opioid abstinence when treated with a 300 mg maintenance dose of SUBLOCADE, compared to the 100 mg dose. While the 300 mg dose did not demonstrate a statistically significant advantage over 100 mg for weekly abstinence—the study’s primary endpoint—in the overall population with moderate to severe opioid use disorder (OUD), the results suggest that higher doses of SUBLOCADE may offer better outcomes for individuals with high levels of fentanyl use.

“These findings offer additional evidence that the higher maintenance dose of SUBLOCADE is safe and may better support patients with intense fentanyl use patterns,” said Christian Heidbreder, Ph.D., Chief Scientific Officer at Indivior. “We aim to provide clinicians with new data that can transform treatment strategies and support patients on their journey to recovery.”

In the Indivior-funded study, patients with OUD who engaged in high-risk opioid use—such as injection use, high opioid dose consumption, or fentanyl use—received two initial 300 mg injections of SUBLOCADE one week apart. They were then randomized to receive eight monthly maintenance doses of either 100 mg or 300 mg. Both dosing regimens led to significant reductions in opioid use: the average weekly use dropped sharply from over 40 instances at screening to fewer than 3 by Week 3, and this improvement was sustained through Week 38. Notably, no new safety concerns were identified with either the 100 mg or 300 mg maintenance doses.

Indivior also funded research exploring OUD treatment access and outcomes in American Indian/Alaska Native (AI/AN) populations, which were presented at CPDD. AI/AN populations experience disproportionate rates of OUD, drug overdose, and gap in access to OUD care. A thematic analysis of focus group research on nine AI/AN advocates indicated that AI/AN people experience significant barriers to accessing medication for opioid use disorder (MOUD).^4-8 Barriers include stigma, institutional challenges, and transitions of care for OUD, highlighting opportunities for culturally appropriate interactive education and institutional advancement.²

These focus group findings are illustrative and can be used to identify avenues for future work, although they may not be generalizable to the full population.

In addition, a large multi-year longitudinal claims database analysis of more than 75,000 AI/AN patients with evidence of OUD showed differences in utilization of MOUD among those seeing Indian Health Services (IHS) vs. non-IHS providers. The majority of patients (73.1%) saw non-IHS providers. Patients treated with any form of MOUD had lower all-cause emergency department vs. those who were not treated with MOUD, highlighting the need for further research to understand MOUD utilization among AI/AN.

"The collective evidence from these presentations highlights prominent barriers to effective care and helps map out appropriate treatment approaches for individuals with OUD in challenging treatment settings," said Heidbreder. “Indivior focuses its scientific, treatment, and policy efforts on helping patients access the medications and support they need to recover.”

Key Abstracts Presented at CPDD:

• Higher Exposures with 300-Mg Buprenorphine Extended-Release (BUP-XR) Increased the Proportion of Responders Among Opioid Use Disorder (OUD) Patients with Heavy Fentanyl Use
• Barriers to and Facilitators of Medication Treatment for Opioid Use Disorder Identified by American Indian/Alaska Native Advocates
• Utilization of Medications for Opioid Use Disorder (MOUD) and Patient Profiles Amongst American Indian/Alaska Native Managing Opioid Use Disorder (OUD)
• Polysubstance Use in Treatment for Opioid Use Disorder: Opioid Abstinence and Alternative Substance Use
• Clinical Outcomes and Recovery in Adults with Opioid Use Disorder: Long-term Treatment with Long- acting Injectable Buprenorphine under Real-World Conditions
• Severity and Symptomatology of Opioid Use Disorder (OUD) Among Individuals Reporting Pain Reliever Use, Pain Reliever Misuse, and/or Heroin Use: A Cross-sectional Analysis of the 2021 and 2022 National Survey on Drug Use and Health

Disclosure:

This press release has been issued by Indivior Inc. and the content has not been approved or authorized by the College on Problems of Drug Dependence.

About SUBLOCADE® 

SUBLOCADE® (buprenorphine extended-release) injection, for subcutaneous use, CIII 

INDICATION AND HIGHLIGHTED SAFETY INFORMATION INDICATION 

SUBLOCADE is indicated for the treatment of moderate to severe opioid use disorder in patients who have initiated treatment with a single dose of a transmucosal buprenorphine product or who are already being treated with buprenorphine. 

SUBLOCADE should be used as part of a complete treatment plan that includes counseling and psychosocial support. 

HIGHLIGHTED SAFETY INFORMATION 

WARNING: RISK OF SERIOUS HARM OR DEATH WITH INTRAVENOUS 

ADMINISTRATION; SUBLOCADE RISK EVALUATION AND MITIGATION STRATEGY 

• Serious harm or death could result if administered intravenously. SUBLOCADE forms a solid mass upon contact with body fluids and may cause occlusion, local tissue damage, and thrombo-embolic events, including life-threatening pulmonary emboli, if administered intravenously. 
• Because of the risk of serious harm or death that could result from intravenous self-administration, SUBLOCADE is only available through a restricted program call the SUBLOCADE REMS Program. Healthcare settings and pharmacies that order and dispense SUBLOCADE must be certified in this program and comply with the REMS requirements. 

CONTRAINDICATIONS 

Hypersensitivity to buprenorphine or any other ingredients in SUBLOCADE. 

WARNINGS AND PRECAUTIONS 

Addiction, Abuse, and Misuse: SUBLOCADE contains buprenorphine, a Schedule III controlled substance that can be abused in a manner similar to other opioids. Monitor patients for conditions indicative of diversion or progression of opioid dependence and addictive behaviors. 

Respiratory Depression: Life threatening respiratory depression and death have occurred in association with buprenorphine. Warn patients of the potential danger of self-administration of benzodiazepines or other CNS depressants while under treatment with SUBLOCADE. 

Risk of Serious Injection Site Reactions: Likelihood of may increase with inadvertent intramuscular or intradermal administration. Evaluate and treat as appropriate. The most common injection site reactions are pain, erythema and pruritus with some involving abscess, ulceration and necrosis. 

Neonatal Opioid Withdrawal Syndrome: Neonatal opioid withdrawal syndrome (NOWS) is an expected and treatable outcome of prolonged use of opioids during pregnancy. 

Adrenal Insufficiency: If diagnosed, treat with physiologic replacement of corticosteroids, and wean patient off of the opioid. 

Risk of Opioid Withdrawal with Abrupt Discontinuation: If treatment with SUBLOCADE is discontinued, monitor patients for several months for withdrawal and treat appropriately. 

Risk of Hepatitis, Hepatic Events: Monitor liver function tests prior to and during treatment. 

Risk of Withdrawal in Patients Dependent on Full Agonist Opioids: Verify that patients have tolerated transmucosal buprenorphine before injecting SUBLOCADE. 

Treatment of Emergent Acute Pain: Treat pain with a non-opioid analgesic whenever possible. If opioid therapy is required, monitor patients closely because higher doses may be required for analgesic effect. 

ADVERSE REACTIONS 

Adverse reactions commonly associated with SUBLOCADE (in ≥5% of subjects) were constipation, headache, nausea, injection site pruritus, vomiting, increased hepatic enzymes, fatigue, and injection site pain. 

For more information about SUBLOCADE, the full Prescribing information including BOXED WARNING, and Medication Guide, visit www.sublocade.com. 

About Opioid Use Disorder (OUD)

Opioid Use Disorder (OUD) is a chronic disease in which people develop a pattern of using opioids that can lead to negative consequences. OUD may affect the parts of the brain that are necessary for life-sustaining functions. 

About Indivior

Indivior is a global pharmaceutical company working to help change patients' lives by developing medicines to treat opioid use disorder (OUD). Our vision is that all patients around the world will have access to evidence-based treatment for OUD and we are dedicated to transforming OUD from a global human crisis to a recognized and treated chronic disease. Building on its global portfolio of OUD treatments, Indivior has a pipeline of product candidates designed to expand on its heritage in this category. Headquartered in the United States in Richmond, VA, Indivior employs over 1,000 individuals globally and its portfolio of products is available in over 30 countries worldwide. Visit www.indivior.com to learn more. Connect with Indivior on LinkedIn by visiting www.linkedin.com/company/indivior.

Media Contact:
IndiviorMediaContacts@indivior.com

1. Higher Exposures with 300-Mg Buprenorphine Extended-Release (BUP-XR) Increased the Proportion of Responders Among Opioid Use Disorder (OUD) Patients with Heavy Fentanyl Use [Late Breaking Oral Sessions]. CPDD Annual Scientific Meeting, June 15, 2025.
2. Barriers To and Facilitators Of Medication Treatment for Opioid Use Disorder Identified by American Indian/Alaska Native Advocates [Oral Session: Expanding SUD interventions across populations]. CPDD Annual Scientific Meeting, June 17, 2025.
3. Utilization of Medications for Opioid Use Disorder (MOUD) and Patient Profiles amongst American Indian/Alaska Native Managing Opioid Use Disorder (OUD) [Poster Session 1]. CPDD Annual Scientific Meeting, June 15, 2025.
4. Indian Health Service. Disparities. 2019. Retrieved from https://www.ihs.gov/newsroom/factsheets/disparities/. Accessed: 16 May 2024.
5. Centers for Disease Control and Prevention, National Center for Health Statistics (2024). Rate of National Drug Overdose Deaths, By Demographic. Available at: https://nida.nih.gov/research-topics/trends- statistics/overdose-death-rates. Accessed: 6 Jun 2024.
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